Luis F. Buenaver, PhD, of the Johns Hopkins University School of Medicine in Baltimore, and colleagues investigated the direct and indirect effect of pain catastrophizing on clinical pain and pain-related interference. A cohort of 214 patients with myofascial temporomandibular disorder was recruited. Study measures included the Pain Catastrophizing Scale, the Pittsburgh Sleep Quality Index, the Brief Pain Inventory, and the Beck Depression Inventory.

The researchers found that pain catastrophizing correlated with greater sleep disturbance. Sleep disturbance accounted for a significant proportion of the pain-catastrophizing-related variance in clinical pain severity and pain-related interference. The rumination component of catastrophizing was indirectly related to clinical outcomes via sleep disturbance. Helplessness and magnification components of catastrophizing had no indirect effect on clinical outcomes.

"To our knowledge, these are the first data to show that pain catastrophizing, and rumination about pain in particular, is associated with clinical pain severity and pain-related interference indirectly through an association with sleep disturbance," the authors write.

One of the authors disclosed financial ties to BMEDI, a company that develops Internet-based behavioral health programs.